MSU Extension Natural Resources

Preface

This citizen's guide to the identification, mapping and management of rooted and some non-rooted aquatic plants is for riparians and others interested in Michigan lakes. It does not replace the advice of a professional aquatic ecologist, which most lake associations will find essential. Effective management requires informed citizens and professional guidance. The purpose of this manual is to help citizens know and understand aquatic plants and work with their professional consultant, contractor, Extension agent and governmental agencies to effectively manage an incredibly valuable resource — their lake.

Rooted aquatic plants include both the attached and free-floating rooted plants. Some of the larger aquatic plants, such as coontail and stonewort, are also included in this guide even though they do not possess true roots. Algae, the small, often microscopic plants, are not addressed in this manual. Though not covered here, the algae are important to the lake ecosystem. Any comprehensive lake management plan will address not only the rooted plants and algae but animal communities, watershed inputs and recreational needs. The lake is a complete ecosystem and should be managed holistically to provide the greatest benefit for present and future generations.

Aquatic plants are a natural and essential part of the lake, just as grasses, shrubs and trees are a natural and essential part of the land. Their roots are a fabric for holding sediments in place, reducing erosion and maintaining bottom stability. They provide habitat for fish, including structure for food organisms, nursery areas, foraging and predator avoidance. Waterfowl, shore birds and aquatic mammals use plants to forage on and within, and as nesting materials and cover. Though plants are important to the lake, overabundant plants can negatively affect fish populations, fishing and the recreational activities of property owners. In this situation, it is advantageous to manage the lake and its aquatic plants for the maximum benefit of all users.

The chapters of this manual cover important topics for understanding aquatic plants. The first seven chapters are building blocks for Chapter 8, the management plan.Working through the chapters, the user will learn to recognize the importance of lake ecology and watershed management (Chapter 1), discern the values of aquatic plants and their interactions in the lake environment (Chapter 2), identify and characterize the common plants of Michigan lakes (Chapter 3), make a plant collection (Chapter 4), map the plants growing in a lake (Chapter 5), secure public input (Chapter 6) and select appropriate management options and tools (Chapter 7). Chapter 8 then guides the user through the development of a plant management plan for the lake.

The purpose of the manual is to assist in the development of a management plan, but the user may employ individual chapters for specific needs. Periodically, the Michigan Lake & Stream Associations, MSU Extension and others may offer training in the use of this manual.

In this edition, updates are provided on herbicides, scientific name changes for plants and the invasive species hydrilla.

Chapter 1. The State of Your Lake and Watershed — A brief introduction to the classification of lakes by trophic state and the importance of watershed management

Chapter 2. Aquatic Plant Communities — An introduction to aquatic plants and how they interact in the lake environment

Chapter 3. Identification and Portraits of the Common Aquatic Plants of Michigan Lakes — A key for and description of the most common species of aquatic plants found in Michigan lakes

Chapter 4. Creating a Plant Collection — Suggestions for building a plant collection that may be used as an educational tool

Chapter 5. Mapping Aquatic Plants in the Lake — Procedures for delineating the lake's plant populations

Chapter 6. Securing Public Input — Information sheets on lake ecology and aquatic plants as well as a citizen survey form for securing input from the public during development of the aquatic plant management plan

Chapter 7. Management Options and Control Tools — Description of ecosystem management philosophies and tools available for promoting and controlling aquatic plants

Chapter 8. The Management Plan — Uses the information generated in Chapters 1-7 to model the development of a plan for managing the lake's aquatic plants.

Printed copies of this publication can be ordered from the MSU Bookstore: https://shop.msu.edu/products/bulletin-wq55